Malicious PDF — malware analysis report

Static analysis result for SHA-256 73c7f087fda9170a…

MALICIOUS

PDF

76.8 KB Created: 2021-09-09 16:37:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 26f22cb2e14bca05b4a3e0b3e3978a84 SHA-1: 2ca6bd796913ddd97d3bfb3cbfc882a5284be2e8 SHA-256: 73c7f087fda9170a85da6b1a9bc254c9187cca03774ec94d31fc8dca4af50919
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple external URIs, with one heuristic specifically identifying it as a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to trick users into downloading a secondary payload via the deceptive links. The presence of embedded JavaScript suggests potential for further malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://thepokewave.com/uploads/files/megim.pdf In PDF document text
    • http://motovelo-nmsk.ru/userfiles/file/guxoginig.pdfIn PDF document text
    • http://daithanhnam.com/upload/files/bazelawuvunisote.pdfIn PDF document text
    • http://doingthing.com/downloads/blog/geust/files/fovuma.pdfIn PDF document text
    • https://aitalk.vn/upload/files/17209141493.pdfIn PDF document text
    • http://yugang360.com/upload_fck/file/2021-9-4/20210904090406843275.pdfIn PDF document text
    • http://kavtas.com/images_upload/files/musebaxorumobojapo.pdfIn PDF document text
    • https://ateliersmq.com/pevron/www/img/file/2490356323.pdfIn PDF document text
    • http://phayaotechno.com/UserFiles/File/mewubafoxisolezawidak.pdfIn PDF document text
    • https://gotoko.com/cmsv2/upload/files/fupefiberitujazo.pdfIn PDF document text
    • http://newmob.it/userfiles/files/65208234952.pdfIn PDF document text
    • http://pomodorolennep.de/gfx/userfiles/files/41027659440.pdfIn PDF document text
    • http://ckrestaurantgroup.com/ckfinder/userfiles/files/74465410055.pdfIn PDF document text
    • http://sakuragiramenandsushi.com/uploads/files/zazetelifazeliwiramob.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1613926e83e463---42951351244.pdfIn PDF document text
    • https://guenangequitation.fr/www/site/js/ckfinder/userfiles/files/85732982178.pdfIn PDF document text
    • http://assotechne.eu/userfiles/files/76742940953.pdfIn PDF document text
    • http://elverum-revmatiker.no/images/file/volubimed.pdfIn PDF document text
    • http://tvkinter.com/file_media/file_image/file/wivetirakurijug.pdfIn PDF document text
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/161378d05bcbd3---nogubijuwo.pdfIn PDF document text
    • https://shian-jin.com/UserFiles/files/66685113916.pdfIn PDF document text
    • http://trieuduong.com/images/Download/wegavekakiwa.pdfIn PDF document text
    • http://abw10thstreetne.com/uploads/files/82461856979.pdfIn PDF document text
    • http://jj-metals.com/userfiles/file/2021090421035173499.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=adblocker+for+chrome+iosPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c79f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC79F 17476 bytes
SHA-256: cbb7e9a8d20deeb7ba035d21d90bcaff1022f9339b5ce5cb18b9869398c41e85
font_01_sfnt_off0000f50a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF50A 10592 bytes
SHA-256: e8112ad2df4e3b89887bde0a8f416754789385efa9b3642d5e38c595cc060dab
font_02_sfnt_off00010d31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D31 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1